Blade Runner makes Olympic history

Oscar Pistorius of South Africa competes in the Men's 400m Round 1 Heats on Day 8 of the London 2012 Olympic Games at Olympic Stadium on August 4, 2012 in London, England. (Photo by Paul Gilham/Getty Images)

LaShawn Merritt (USA) walks off the track with a hamstring injury in the men's 400m heats during the London 2012 Olympic Games at Olympic Stadium. (Kirby Lee-USA TODAY Sports)

LONDON -- Oscar Pistorius of South Africa became the first amputee to compete on the track at an Olympics Saturday, finishing second in his 400-meter heat to advance to the next round.

Pistorius, a double-amputee who runs on carbon-fiber blades, circled the oval in 45.44 seconds, good enough for a berth in the semifinals Sunday night. Because of the blades he wears Pistorius is known as "Blade Runner."

Defending champion LaShawn Merritt of the U.S., who has been bothered by an injured left hamstring, pulled up in the backstretch of his 400-meter preliminary heat. Merritt got off to a bad start, fell behind early and stopped running after about 200 meters. The gold medal favorite, who hurt himself in a tuneup race, limped slowly off the track.

In the 100 meter race, defending Olympic champion Usain Bolt of Jamaica won his heat. His time was 10.09 seconds.

Bolt dominated the Beijing Games four years ago, winning golds in world-record times in the 100, 200 and 4x100 relay, something no man had ever done at an Olympics. At the 2009 world championships, he lowered his 100 mark to 9.58, which still stands.